"He was just a terrific person to work with," Lansbury tells TVGuide.com of her late Murder co-star. "He was an actor's actor. He felt that the [happier] the atmosphere on the set was, the more we would get done. And of course, he was right. When I say 'get done,' he knew it was what was on the screen that counted, and his manner and his way of working with other actors was very generous and very understanding. We had new cast coming in every single week and yet we were always playing the same people. Tom was really a consummate actor."Bosley died Tuesday at 83 of heart failure after a battle with lung cancer. Lansbury says she hadn't seen Bosley in the last six years, as she returned to theater, but knew that his cancer battle "really took a great deal out of him." "I wouldn't have hardly ever recognized him — the wonderfully ebullient man that I had known as Sheriff Tupper," she says.

Before they teamed up as Jessica Fletcher and Sheriff Amos Tupper on the long-running CBS drama in 1984, the two worked together 20 years earlier in The World of Henry Orient, in which Bosley played Lansbury's husband. "I had the joy of working with him in film all those years prior, which was wonderful," Lansbury says. "I never did see him in [his Tony-winning role in] Fiorello!, but his performance was legendary. We all knew we were working with a real pro. He's a family man, he loved his family, and he was very, very warm towards everybody who he worked with."Though Bosley is better-known as one of TV's ultimate dads, Happy Days' Mr. Cunningham, Lansbury, 85, admits she never watched the sitcom, as she was working in theater during the show's run ("I missed a whole generation of television. Oh my God, I never saw Taxi!"). But the five-time Tony winner, who plans to return to Broadway next year, is "thrilled" that they made their own stamp on prime time with Murder.

"He was very much responsible in helping me launch that series. He has to have to credit for it," Lansbury says. "I'm not great for anecdotes — the men are wonderful at remembering these things — but I just have a lovely memory of a very dear person who I was extremely fond of. I certainly send my love and condolences to his family. They knew what a gem they had."